EP1652286B1 - Switched-mode power supply - Google Patents
Switched-mode power supply Download PDFInfo
- Publication number
- EP1652286B1 EP1652286B1 EP04737408A EP04737408A EP1652286B1 EP 1652286 B1 EP1652286 B1 EP 1652286B1 EP 04737408 A EP04737408 A EP 04737408A EP 04737408 A EP04737408 A EP 04737408A EP 1652286 B1 EP1652286 B1 EP 1652286B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- voltage
- auxiliary
- switched
- power supply
- mode power
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Not-in-force
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/36—Means for starting or stopping converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0006—Arrangements for supplying an adequate voltage to the control circuit of converters
Definitions
- the invention relates to a switching power supply for converting a DC input voltage into an output voltage having a drive circuit for driving at least one controlled switch, which periodically applies the input voltage to at least one primary winding of a transformer, wherein an auxiliary voltage for the drive circuit by means of a semiconductor auxiliary switch at falling the input voltage can be switched off below a predefinable minimum value, wherein the auxiliary voltage is, on the one hand, a first auxiliary supply voltage derived from the input voltage and, on the other hand, a second auxiliary supply voltage derived from an auxiliary winding of the transformer by rectification.
- the drive circuit first obtains the auxiliary supply voltage required for its operation when starting up from a lying over a high-impedance current path from the input voltage auxiliary voltage sensor as the first auxiliary power source, partly during startup and then from an auxiliary winding of the transformer for rectification and control means a longitudinal regulator as a second auxiliary power source.
- a constant power supply of the drive circuit via the input voltage which is usually obtained by rectifying an AC line voltage and often called DC link voltage, would lead to undesirable losses in the series resistor, since the input voltage can be up to 370 volts and more, but the supply voltage of the drive circuit, for example, only is at 15 volts, so that the voltage difference must be at the resistor and even with only low power consumption of the drive circuit of z.
- B. 10 mA the power to be destroyed would amount to a few watts.
- Such a switching power supply is from the EP 0 585 788 A1 known, wherein a primary-side auxiliary power source is provided by means of a transistor circuit. A pulse width modulator is supplied by means of a primary-side auxiliary supply source until a secondary-side auxiliary voltage is available.
- a switching power supply with a primary-side and a secondary-side auxiliary voltage source is also from the US 5,841,641 , A known
- the problem underlying the invention assumes that when the input DC voltage drops below a certain value, for. B. 100 volts, the power supply of the drive circuit should be interrupted so that the switching power supply shut down is. Otherwise, no proper operation would be possible, it would be z. For example, to the limits of the duty cycle of the drive pulse for the switch, too high currents, etc. Furthermore, said threshold voltage value at which off or to be turned on again, must be subject to a hysteresis, otherwise it would lead to instabilities.
- FIG. 1 The circuit of a switching power supply according to the prior art, in which said switching off or turning back on the supply voltage of the drive circuit is possible is in Fig. 1 shown.
- a DC input voltage Uzk which has been obtained, for example, by rectifying an AC line voltage and whose nominal range is for example between 120 and 370 volts, can be connected via a controlled switch S to a primary winding Wp of a transformer UET.
- the switched current thereby flows through a sensor resistor Rsh, from which information corresponding to the current is supplied to a drive circuit AST, which supplies a control pulse to the control electrode of the controlled switch S.
- the voltage of a secondary winding Ws of the transformer is rectified by means of a rectifier diode Dg, smoothed on a capacitor Ca and is available as an output voltage Ua.
- the information of a lying at the output voltage Ua voltage sensor PLC is supplied via an optocoupler OKO the drive circuit AST, so that a regulation of the output voltage by a corresponding change in the duty cycle of the drive pulse for the switch S is possible.
- the drive circuit AST has an input H for its operating voltage, hereinafter referred to as auxiliary supply voltage.
- This auxiliary supply voltage is, as already mentioned above, obtained in two ways.
- a voltage is available which is connected to an auxiliary voltage capacitor Cs and is obtained with the aid of a high-impedance current path, here a high-impedance series resistor Rs.
- This voltage is designated here by Uh and it is guided over the switching path of a semiconductor auxiliary switch Ts to said voltage supply input H of the drive circuit AST.
- an auxiliary winding W1 supplies a voltage which is rectified by means of a rectifier diode D and smoothed on a capacitor C. This voltage is also passed via a series regulator LAE and a decoupling diode De to the supply input H of the drive circuit AST.
- a comparator COM is provided, the output of which is guided to the switching input of the auxiliary switch Ts, here to the base.
- the positive input of the comparator KOM is connected to the reference voltage Uref generated by a Zener diode Zref.
- the Zener diode Zref receives its current through a resistor R, at which the auxiliary supply voltages Uh and Uh1 are located. At the positive entrance of the comparator KOM is thus a voltage which corresponds to the current auxiliary voltage.
- a voltage which is obtained by means of a voltage divider Ra, Rb from the input voltage Uzk.
- a resistance network is provided which determines the hysteresis behavior of the comparator KOM.
- the comparator KOM turns off the auxiliary switch Ts and thus the auxiliary supply voltage from the drive circuit AST, which then no longer clocks and the entire switching power supply stops its power supply operation. If the supply voltage Uzk then increases again, however, the comparator KOM switches through the auxiliary switch Ts again with a hysteresis of, for example, 20 volts, which then takes place at an input voltage Uzk of 120 volts in accordance with the aforementioned exemplary hysteresis.
- An object of the invention is to find a circuit for the controlled switching on and off of the auxiliary supply voltage which has a lower power consumption and is simpler in construction.
- control electrode of the auxiliary switch on the one hand connected to a reference voltage output of a drive circuit internally generated reference voltage and on the other hand to a divider of an input voltage divider, so when working drive circuit, the control electrode an additional voltage in Sense of driving through the auxiliary switch receives.
- the circuit according to the invention does not require a comparator and therefore also not the current-distorting elements on the input circuit of such a comparator. It is simple and cheap in construction and the power loss can be significantly reduced.
- a decoupling resistor is connected between the reference voltage output and the control electrode of the auxiliary switch.
- the decoupling resistor between the reference voltage output and the divider point of a voltage divider is expedient if the decoupling resistor between the reference voltage output and the divider point of a voltage divider is.
- the input voltage is connected via the series connection of two resistors to an auxiliary voltage capacitor, from where the auxiliary voltage reaches the auxiliary voltage input of the drive circuit via the switching path of the auxiliary switch , And connected to the junction of the two resistors of the series connection of the input voltage divider for the control electrode of the auxiliary switch.
- high-resistance (power) resistors technically mostly consist of the series connection of two or more resistors.
- the reference voltage at the reference voltage output of the drive circuit is switched on or off when the supply voltage of the drive circuit exceeds or falls below a threshold value. It is advisable to switch the reference voltage on or off with hysteresis.
- a drive circuit AST is required for the invention in which a reference voltage Uref is available at a reference output R, this reference voltage being switched on or off as soon as the supply voltage of the drive circuit exceeds / falls below a threshold value, whereby a hysteresis may be present.
- Commercially available drive circuits AST all have such a reference voltage but have not heretofore been used for the purpose described below.
- the reference voltage Uref of the drive circuit AST is supplied via a decoupling resistor Rf to the control electrode, here the gate, of the auxiliary switch Ts.
- a decoupling resistor Rf to the control electrode, here the gate, of the auxiliary switch Ts.
- the control electrode G of the auxiliary switch Ts is on the other hand at the divider point Te of an input voltage divider, which is here formed by a resistor RS1, a resistor R1 and a resistor R2.
- the resistor R1 could also be connected directly to the input voltage Uzk.
- Another resistor RS2 connects the resistor RS1 to the capacitor CS for the auxiliary supply voltage Uh.
- the internal reference voltage Uref is available at the output R and a corresponding voltage or a proportional part thereof is applied to the branch R2 of the voltage divider RS1, R1, R2, which in turn impresses the voltage the gate G of the auxiliary switch Ts is raised.
- the linear regulator LAE takes over the auxiliary supply with its output voltage UH1.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
Description
Die Erfindung bezieht sich auf ein Schaltnetzteil zum Wandeln einer Eingangsgleichspannung in eine Ausgangsspannung mit einer Ansteuerschaltung zum Ansteuern zumindest eines gesteuerten Schalters, welcher die Eingangsspannung periodisch an zumindest eine Primärwicklung eines Übertragers legt, wobei eine Hilfsspannung für die Ansteuerschaltung mit Hilfe eines Halbleiter-Hilfsschalters bei Abfallen der Eingangsspannung unter einen vorgebbaren Mindestwert abschaltbar ist, wobei die Hilfsspannung einerseits eine aus der Eingangsspannung abgeleitete erste Hilfsversorgungsspannung und andererseits eine von einer Hilfswicklung des Übertragers durch Gleichrichten abgeleitete zweite Hilfsversorgungsspannung ist.The invention relates to a switching power supply for converting a DC input voltage into an output voltage having a drive circuit for driving at least one controlled switch, which periodically applies the input voltage to at least one primary winding of a transformer, wherein an auxiliary voltage for the drive circuit by means of a semiconductor auxiliary switch at falling the input voltage can be switched off below a predefinable minimum value, wherein the auxiliary voltage is, on the one hand, a first auxiliary supply voltage derived from the input voltage and, on the other hand, a second auxiliary supply voltage derived from an auxiliary winding of the transformer by rectification.
Bei Schaltnetzteilen der gegenständlichen Art bezieht die Ansteuerschaltung die für ihren Betrieb erforderliche Hilfsversorgungsspannung zunächst beim Hochlaufen aus einem über einen hochohmigen Strompfad aus der Eingangsspannung liegenden Hilfsspannungskandensator als erste Hilfsversorgungsquelle, zum Teil während des Hochlaufens und danach jedoch aus einer Hilfswicklung des Übertragers nach Gleichrichtung und Regelung mittels eines Längsreglers als zweite Hilfsversorgungsquelle. Eine ständige Spannungsversorgung der Ansteuerschaltung über die Eingangsspannung, welche meist durch Gleichrichten einer Netzwechselspannung gewonnen und oft Zwischenkreisspannung genannt wird, würde zu unerwünschten Verlusten in dem Vorwiderstand führten, da die Eingangsspannung bis zu 370 Volt und mehr betragen kann, die Versorgungsspannung der Ansteuerschaltung jedoch beispielsweise nur bei 15 Volt liegt, sodass die Spannungsdifferenz an dem Vorwiderstand liegen muss und auch bei nur geringer Stromaufnahme der Ansteuerschaltung von z. B. 10 mA die zu vernichtende Leistung einige Watt betragen würde.In switched-mode power supplies of the subject type, the drive circuit first obtains the auxiliary supply voltage required for its operation when starting up from a lying over a high-impedance current path from the input voltage auxiliary voltage sensor as the first auxiliary power source, partly during startup and then from an auxiliary winding of the transformer for rectification and control means a longitudinal regulator as a second auxiliary power source. A constant power supply of the drive circuit via the input voltage, which is usually obtained by rectifying an AC line voltage and often called DC link voltage, would lead to undesirable losses in the series resistor, since the input voltage can be up to 370 volts and more, but the supply voltage of the drive circuit, for example, only is at 15 volts, so that the voltage difference must be at the resistor and even with only low power consumption of the drive circuit of z. B. 10 mA the power to be destroyed would amount to a few watts.
Ein solches Schaltnetzteil ist aus der
Das der Erfindung zugrunde liegende Problem geht davon aus, dass bei Absinken der Eingangsgleichspannung unter einen bestimmten Wert, z. B. 100 Volt, die Spannungsversorgung der Ansteuerschaltung unterbrochen werden soll, damit das Schaltnetzteil stillgelegt ist. Anderenfalls wäre kein ordungsgemäßer Betrieb möglich, es käme z. B. zu den Grenzen des Tastverhältnisses des Ansteuerpulses für den Schalter, zu hohen Strömen, etc. Weiters muss der genannte Schwellspannungswert, bei welchem aus- bzw. wieder eingeschaltet werden soll, mit einer Hysterese behaftet sein, sonst käme es zu Instabilitäten.The problem underlying the invention assumes that when the input DC voltage drops below a certain value, for. B. 100 volts, the power supply of the drive circuit should be interrupted so that the switching power supply shut down is. Otherwise, no proper operation would be possible, it would be z. For example, to the limits of the duty cycle of the drive pulse for the switch, too high currents, etc. Furthermore, said threshold voltage value at which off or to be turned on again, must be subject to a hysteresis, otherwise it would lead to instabilities.
Die Schaltung eines Schaltnetzteils nach dem Stand der Technik, bei welchem das genannte Abschalten bzw. wieder Einschalten der Versorgungsspannung der Ansteuerschaltung möglich ist, ist in
Die Ansteuerschaltung AST besitzt einen Eingang H für ihre Betriebsspannung, im Folgenden Hilfsversorgungsspannung genannt. Diese Hilfsversorgungsspannung wird, wie bereits oben erwähnt, auf zweierlei Art gewonnen.The drive circuit AST has an input H for its operating voltage, hereinafter referred to as auxiliary supply voltage. This auxiliary supply voltage is, as already mentioned above, obtained in two ways.
Während der Anlaufphase der Ansteuerschaltung bzw. des Schaltnetzteils ganz allgemein steht eine Spannung zur Verfügung, die an einem Hilfsspannungskondensator Cs liegt und mit Hilfe eines hochohmigen Strompfades, hier eines hochohmigen Vorwiderstandes Rs, gewonnen wird. Diese Spannung ist hier mit Uh bezeichnet und sie wird über die Schaltstrecke eines Halbleiter-Hilfsschalters Ts zu dem genannten Spannungsversorgungseingang H der Ansteuerschaltung AST geführt.During the start-up phase of the drive circuit or of the switched-mode power supply in general, a voltage is available which is connected to an auxiliary voltage capacitor Cs and is obtained with the aid of a high-impedance current path, here a high-impedance series resistor Rs. This voltage is designated here by Uh and it is guided over the switching path of a semiconductor auxiliary switch Ts to said voltage supply input H of the drive circuit AST.
Während des Betriebes des Schaltnetzteils liefert eine Hilfswicklung W1 eine Spannung, die mit Hilfe einer Gleichrichterdiode D gleichgerichtet und an einem Kondensator C geglättet wird. Diese Spannung wird über einen Längsregler LAE und eine Entkopplungsdiode De gleichfalls zu dem Versorgungseingang H der Ansteuerschaltung AST geführt.During operation of the switched-mode power supply, an auxiliary winding W1 supplies a voltage which is rectified by means of a rectifier diode D and smoothed on a capacitor C. This voltage is also passed via a series regulator LAE and a decoupling diode De to the supply input H of the drive circuit AST.
Um das hysteresebehaftete Aus- bzw. Einschalten des Hilfsschalters Ts, der hier einen Basis-Emitterwiderstand Rbe aufweist, zu ermöglichen, ist ein Komparator KOM vorgesehen, dessen Ausgang zu dem Schalteingang des Hilfsschalters Ts, hier zur Basis, geführt ist. Der positive Eingang des Komparators KOM liegt an der von einer Zenerdiode Zref erzeugten Referenzspannung Uref. Die Zenerdiode Zref erhält ihren Strom über einen Widerstand R, an dem die Hilfsversorgungsspannungen Uh bzw. Uh1 liegen. An dem positiven Eingang des Komparators KOM liegt somit eine Spannung welche der aktuellen Hilfsspannung entspricht. An dem negativen Eingang des Komparators KOM liegt eine Spannung, die mit Hilfe eines Spannungsteilers Ra, Rb aus der Eingangsspannung Uzk erhalten wird. Im Mitkopplungszweig des Komparators KOM ist ein Widerstandsnetzwerk vorgesehen, welches das Hystereseverhalten des Komparators KOM bestimmt.In order to enable the hysteresis off or on of the auxiliary switch Ts, which here has a base-emitter resistor Rbe, a comparator COM is provided, the output of which is guided to the switching input of the auxiliary switch Ts, here to the base. The positive input of the comparator KOM is connected to the reference voltage Uref generated by a Zener diode Zref. The Zener diode Zref receives its current through a resistor R, at which the auxiliary supply voltages Uh and Uh1 are located. At the positive entrance of the comparator KOM is thus a voltage which corresponds to the current auxiliary voltage. At the negative input of the comparator KOM is a voltage which is obtained by means of a voltage divider Ra, Rb from the input voltage Uzk. In the feed-forward branch of the comparator KOM, a resistance network is provided which determines the hysteresis behavior of the comparator KOM.
Sinkt bei dieser Schaltung des Schaltnetzteils die Eingangsspannung Uzk unter einen durch die Referenzdiode Zref vorgegebenen Wert, z. B.100 Volt, so schaltet der Komparator KOM den Hilfsschalter Ts aus und damit die Hilfsversorgungsspannung von der Ansteuerschaltung AST ab, welche sodann nicht mehr taktet und das gesamte Schaltnetzteil stellt seinen Stromversorgungsbetrieb ein. Steigt die Versorgungsspannung Uzk danach wieder an, so schaltet der Komparator KOM jedoch mit einer Hysterese von beispielsweise 20 Volt, den Hilfsschalter Ts wieder durch, was entsprechend der genannten beispielsweisen Hysterese dann bei einer Eingangsspannung Uzk von 120 Volt erfolgt.Decreases in this circuit of the switching power supply, the input voltage Uzk below a predetermined by the reference diode Zref value, z. B.100 volts, the comparator KOM turns off the auxiliary switch Ts and thus the auxiliary supply voltage from the drive circuit AST, which then no longer clocks and the entire switching power supply stops its power supply operation. If the supply voltage Uzk then increases again, however, the comparator KOM switches through the auxiliary switch Ts again with a hysteresis of, for example, 20 volts, which then takes place at an input voltage Uzk of 120 volts in accordance with the aforementioned exemplary hysteresis.
Wenngleich durch diese Schaltung die gewünschte Funktion des Aus- bzw. wieder Einschaltens sicher gestellt ist, ist daran der relativ hohe Stromverbrauch (Verlustleistung) der benötigten Bauteile nachteilig, ebenso der Platzbedarf der Bauteile.Although the desired function of switching off and on again is ensured by this circuit, the relatively high power consumption (power loss) of the required components is disadvantageous, as is the space requirement of the components.
Eine Aufgabe der Erfindung liegt darin, eine Schaltung für das gesteuerte Ein- bzw. Ausschalten der Hilfsversorgungsspannung zu finden welche einen geringeren Stromverbrauch aufweist und einfacher im Aufbau ist.An object of the invention is to find a circuit for the controlled switching on and off of the auxiliary supply voltage which has a lower power consumption and is simpler in construction.
Diese Aufgabe wird mit einem Schaltnetzteil der eingangs genannten Art gelöst, bei welchem erfindungsgemäß die Steuerelektrode des Hilfsschalters einerseits mit einem Referenzspannungsausgang einer in der Ansteuerschaltung intern erzeugten Referenzspannung und andererseits mit einem Teilerpunkt eines Eingangsspannungsteilers verbunden ist, sodass bei arbeitender Ansteuerschaltung die Steuerelektrode eine zusätzliche Spannung im Sinne eines Durchsteuerns des Hilfsschalters erhält.This object is achieved with a switching power supply of the type mentioned, in which according to the invention, the control electrode of the auxiliary switch on the one hand connected to a reference voltage output of a drive circuit internally generated reference voltage and on the other hand to a divider of an input voltage divider, so when working drive circuit, the control electrode an additional voltage in Sense of driving through the auxiliary switch receives.
Die Schaltung nach der Erfindung benötigt keinen Komparator und somit auch nicht die stromverzerhenden Elemente an der Eingangsbeschaltung eines solchen Komparators. Sie ist einfach und billig im Aufbau und die Verlustleistung kann erheblich gesenkt werden.The circuit according to the invention does not require a comparator and therefore also not the current-distorting elements on the input circuit of such a comparator. It is simple and cheap in construction and the power loss can be significantly reduced.
Um Rückwirkungen auf den Schaltregler zu vermeiden, ist bei einer vorteilhaften Ausführungsform der Erfindung vorgesehen, dass zwischen Referenzspannungsausgang und Steuerelektrode des Hilfsschalters ein Entkopplungswiderstand geschaltet ist.In order to avoid repercussions on the switching regulator, it is provided in an advantageous embodiment of the invention that a decoupling resistor is connected between the reference voltage output and the control electrode of the auxiliary switch.
Im Sinne einer freieren Wahl der Einschalt/Ausschaltschwelle des Hilfsschalters ist es zweckmäßig, wenn der Entkopplungswiderstand zwischen Referenzspannungsausgang und dem Teilerpunkt eines Spannungsteilers liegt.In terms of a freer choice of the on / off threshold of the auxiliary switch, it is expedient if the decoupling resistor between the reference voltage output and the divider point of a voltage divider is.
Um mit möglichst wenigen Schaltelementen das Auslangen zu finden und dennoch eine sichere Funktion zu erreichen, ist es zweckmäßig, wenn die Eingangsspannung über die Serienschaltung zweier Widerstände zu einem Hilfsspannungskondensator geführt ist, von wo die Hilfsspannung über die Schaltstrecke des Hilfsschalters zu dem Hilfsspannungseingang der Ansteuerschaltung gelangt, und an den Verbindungspunkt der beiden Widerstände der Serienschaltung der Eingangsspannungsteiler für die Steuerelektrode des Hilfsschalters angeschlossen ist. Dies nimmt auf den Umstand Rücksicht, dass hochohmige (Leistungs)widerstände technisch meist aus der Serienschaltung von zwei oder mehr Widerständen bestehen.In order to find with as few switching elements Auslangen and yet to achieve a safe function, it is advantageous if the input voltage is connected via the series connection of two resistors to an auxiliary voltage capacitor, from where the auxiliary voltage reaches the auxiliary voltage input of the drive circuit via the switching path of the auxiliary switch , And connected to the junction of the two resistors of the series connection of the input voltage divider for the control electrode of the auxiliary switch. This takes into account the fact that high-resistance (power) resistors technically mostly consist of the series connection of two or more resistors.
Um ein gut definiertes Ablösen der Spannungsversorgung auf dem Längsregler bzw. umgekehrt zu ermöglichen, ist es vorteilhaft, wenn die Referenzspannung an dem Referenzspannungsausgang der Ansteuerschaltung ein- bzw. abgeschaltet ist, wenn die Versorgungsspannung der Ansteuerschaltung einen Schwellwert über- bzw. unterschreitet. Dabei ist es empfehlenswert, wenn das Ein- bzw. Abschalten der Referenzspannung mit Hysterese erfolgt.In order to enable a well-defined detachment of the voltage supply to the series regulator or vice versa, it is advantageous if the reference voltage at the reference voltage output of the drive circuit is switched on or off when the supply voltage of the drive circuit exceeds or falls below a threshold value. It is advisable to switch the reference voltage on or off with hysteresis.
Die Erfindung samt weiterer Vorteile ist im Folgenden anhand einer beispielsweisen Ausführungsform näher erläutert, die in der Zeichnung veranschaulicht ist. In dieser zeigen:
- ■ Fig.1
- die bereits weiter oben beschriebene Schaltung eines Schaltnetzteils nach dem Stand der Technik und
- ■ Fig. 2
- die Schaltung eines Schaltnetzteils nach der Erfindung.
- ■ Fig.1
- the already described above circuit of a switching power supply according to the prior art and
- ■ Fig. 2
- the circuit of a switching power supply according to the invention.
Die Schaltung nach
Die Steuerelektrode G des Hilfsschalters Ts liegt andererseits an dem Teilerpunkt Te eines Eingangsspannungsteilers, der hier von einem Widerstand RS1, einem Widerstand R1 und einem Widerstand R2 gebildet ist. Alternativ könnte der Widerstand R1 auch direkt an die Eingangsspannung Uzk geschaltet sein. Ein weiterer Widerstand RS2 verbindet den Widerstand RS1 mit dem Kondensator CS für die Hilfsversorgungsspannung Uh. Bei der Schaltung nach
Die in
Sobald die Ansteuerschaltung AST zu arbeiten beginnt bzw. kurz darauf steht die interne Referenzspannung Uref an dem Ausgang R zur Verfügung und eine entsprechende Spannung bzw. ein ihr proportionaler Teil wird dem Zweig R2 des Spannungsteilers RS1, R1, R2 aufgeprägt, wodurch wiederum die Spannung an dem Gate G des Hilfsschalters Ts angehoben wird. Schließlich übernimmt der Längsregler LAE mit seiner Ausgangsspannung UH1 die Hilfsversorgung.As soon as the drive circuit AST begins to operate or shortly thereafter, the internal reference voltage Uref is available at the output R and a corresponding voltage or a proportional part thereof is applied to the branch R2 of the voltage divider RS1, R1, R2, which in turn impresses the voltage the gate G of the auxiliary switch Ts is raised. Finally, the linear regulator LAE takes over the auxiliary supply with its output voltage UH1.
Sinkt die Eingangsspannung Uzk, so sinkt die Spannung am Gate G des Hilfsschalters Ts proportional und dementsprechend, um 2 bis 3 Volt verringert, die Spannung am Source S. Ab einer bestimmten Spannung an dem Punkt Te des Eingangsspannungsteilers hört die Ansteuerschaltung zu arbeiten auf und die Referenzspannung Uref am Ausgang R bricht zusammen. Dadurch wird der Spannungsteilerpunkt Te noch weiter ins Negative gezogen und das Abschalten noch besser gesichert. Auf diese Weise ergibt sich auch die geforderte Hysterese betreffend das Ab- bzw. Einschalten.When the input voltage Uzk drops, the voltage at the gate G of the auxiliary switch Ts decreases proportionally and accordingly decreases by 2 to 3 volts, the voltage at the source S. From a certain voltage at the point Te of the input voltage divider, the drive circuit ceases to operate and Reference voltage Uref at output R breaks down. As a result, the voltage divider point Te is pulled even further into negative and the shutdown even better secured. In this way, there is also the required hysteresis on the off or on.
Claims (6)
- Switched-mode power supply for converting a DC input voltage (Uzk) into an output voltage (Ua), said switched-mode power supply having a trigger circuit (AST) for triggering at least one controlled switch (S) that periodically applies the input voltage to at least one primary winding (Wp) of a transformer (UET), wherein an auxiliary voltage for the trigger circuit can be switched off with the aid of an auxiliary semiconductor switch (Ts) when the input voltage drops below a predefinable minimum value, wherein the auxiliary voltage is on the one hand a first auxiliary supply voltage (Uh) derived from the input voltage and on the other hand a second auxiliary supply voltage (Uh1) derived from an auxiliary winding (Wh) of the transformer by means of rectification,
characterised in that
the gate electrode (G) of the auxiliary switch (Ts) is connected on the one hand to a reference voltage output (R) of a reference voltage (Uref) generated internally in the trigger circuit (AST) and on the other hand to a divider point (Te) of an input voltage divider (Rs1, R1, R2) such that when the trigger circuit is operative the gate electrode (G) of the auxiliary switch (Ts) receives an additional voltage in the sense of a forced tripping of the auxiliary switch (Ts). - Switched-mode power supply according to claim 1, characterised in that a decoupling resistor (Rf) is connected between reference voltage output (R) and gate electrode (G) of the auxiliary switch (Ts).
- Switched-mode power supply according to claim 2, characterised in that the decoupling resistor (Rf) is disposed between reference voltage output (R) and the divider point (Tf) of a voltage divider (R3/R4).
- Switched-mode power supply according to one of claims 1 to 3, characterised in that the input voltage (Uzk) is routed via the series connection of two resistors (RS1, RS2) to an auxiliary voltage capacitor (Cs) from where the auxiliary voltage (Uh) travels across the breaker gap of the auxiliary switch (Ts) to the auxiliary voltage input (H) of the trigger circuit (AST) and is connected to the interconnection point of the two resistors (RS1, RS2) of the series connection of the input voltage dividers (R1, R2) for the gate electrode (G) of the auxiliary switch (Ts).
- Switched-mode power supply according to one of claims 1 to 4, characterised in that the reference voltage (Uref) at the reference voltage output (R) of the trigger circuit (AST) is switched on and off respectively if the supply voltage of the trigger circuit exceeds or falls below a threshold value.
- Switched-mode power supply according to claim 5, characterised in that the reference voltage (Uref) is switched on and off with hysteresis.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT0124503A AT413910B (en) | 2003-08-06 | 2003-08-06 | POWER SUPPLY |
PCT/AT2004/000278 WO2005015720A1 (en) | 2003-08-06 | 2004-08-05 | Switched-mode power supply |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1652286A1 EP1652286A1 (en) | 2006-05-03 |
EP1652286B1 true EP1652286B1 (en) | 2011-10-05 |
Family
ID=34120303
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP04737408A Not-in-force EP1652286B1 (en) | 2003-08-06 | 2004-08-05 | Switched-mode power supply |
Country Status (5)
Country | Link |
---|---|
US (1) | US7365996B2 (en) |
EP (1) | EP1652286B1 (en) |
CN (1) | CN100440696C (en) |
AT (2) | AT413910B (en) |
WO (1) | WO2005015720A1 (en) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006106040A1 (en) * | 2005-04-08 | 2006-10-12 | SIEMENS AKTIENGESELLSCHAFT öSTERREICH | Method for operating a switched mode power supply with the recovery of primary scattered energy |
US8451627B2 (en) | 2007-11-16 | 2013-05-28 | Itron, Inc. | Devices and methods for converting alternating current (AC) power to direct current (DC) power |
DE102007058377A1 (en) * | 2007-12-05 | 2009-06-10 | BSH Bosch und Siemens Hausgeräte GmbH | Circuit arrangement for operating a household appliance |
US8773869B2 (en) * | 2010-03-29 | 2014-07-08 | Itron, Inc. | System and method for conversion of high voltage AC to low voltage DC using input voltage gating |
US9048747B2 (en) | 2011-11-23 | 2015-06-02 | Zahid Ansari | Switched-mode power supply startup circuit, method, and system incorporating same |
JP6991832B2 (en) * | 2017-10-30 | 2022-01-13 | キヤノン株式会社 | Power supply and image forming equipment |
Family Cites Families (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3887888D1 (en) * | 1988-09-30 | 1994-03-24 | Siemens Ag | Primary switched mode power supply. |
US5014178A (en) * | 1990-05-14 | 1991-05-07 | Power Integrations, Inc. | Self powering technique for integrated switched mode power supply |
US5206800A (en) * | 1991-03-13 | 1993-04-27 | Astec International, Ltd. | Zero voltage switching power converter with secondary side regulation |
US5285369A (en) * | 1992-09-01 | 1994-02-08 | Power Integrations, Inc. | Switched mode power supply integrated circuit with start-up self-biasing |
JP2767781B2 (en) * | 1993-09-17 | 1998-06-18 | 東光株式会社 | AC-DC converter |
DE59305657D1 (en) * | 1993-12-10 | 1997-04-10 | Siemens Ag | Clocked converter with optocoupler |
US5459652A (en) * | 1994-01-28 | 1995-10-17 | Compaq Computer Corp. | Boot strap circuit for power up control of power supplies |
JP3107193B2 (en) * | 1995-12-28 | 2000-11-06 | サンケン電気株式会社 | DC-DC converter |
US5841641A (en) * | 1996-05-01 | 1998-11-24 | Compaq Computer Corporation | Protected zero-crossing detection using switching transistor's on-resistance |
EP1160963A3 (en) * | 2000-05-31 | 2004-02-04 | Sanken Electric Co., Ltd. | DC-to-DC converter |
AT410619B (en) * | 2000-07-14 | 2003-06-25 | Siemens Ag Oesterreich | METHOD FOR DETECTING AND / OR LIMITING THE SHORT CIRCUIT STATES OF A SWITCHING CONVERTER |
AT410867B (en) * | 2001-04-06 | 2003-08-25 | Siemens Ag Oesterreich | POWER SUPPLY WITH SHUT-OFF PROTECTION |
JP3578113B2 (en) * | 2001-05-29 | 2004-10-20 | 株式会社村田製作所 | Switching power supply |
CN1400732A (en) * | 2001-08-03 | 2003-03-05 | 致伸科技股份有限公司 | Power-switching circuit |
AT502302A1 (en) * | 2002-02-22 | 2007-02-15 | Siemens Ag Oesterreich | DRIVE SYSTEM |
AT413617B (en) * | 2002-05-14 | 2006-04-15 | Siemens Ag Oesterreich | CHARGING POWER SUPPLY |
AT412693B (en) * | 2002-09-20 | 2005-05-25 | Siemens Ag Oesterreich | METHOD FOR CONTROLLING SHUT-OFF IN OVERLOAD STATES OF A SWITCHING POWER SUPPLY |
JP3861871B2 (en) * | 2003-11-26 | 2006-12-27 | サンケン電気株式会社 | Switching power supply |
-
2003
- 2003-08-06 AT AT0124503A patent/AT413910B/en not_active IP Right Cessation
-
2004
- 2004-08-05 CN CNB2004800223324A patent/CN100440696C/en not_active Expired - Fee Related
- 2004-08-05 WO PCT/AT2004/000278 patent/WO2005015720A1/en active Application Filing
- 2004-08-05 EP EP04737408A patent/EP1652286B1/en not_active Not-in-force
- 2004-08-05 AT AT04737408T patent/ATE527744T1/en active
-
2006
- 2006-02-01 US US11/344,615 patent/US7365996B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
WO2005015720A1 (en) | 2005-02-17 |
CN100440696C (en) | 2008-12-03 |
CN1833348A (en) | 2006-09-13 |
EP1652286A1 (en) | 2006-05-03 |
ATE527744T1 (en) | 2011-10-15 |
AT413910B (en) | 2006-07-15 |
ATA12452003A (en) | 2005-10-15 |
US20060215423A1 (en) | 2006-09-28 |
US7365996B2 (en) | 2008-04-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE10040413B4 (en) | Circuit arrangement for generating a switching signal for a current-controlled switching power supply | |
EP0396125B1 (en) | Forward conventer | |
DE102017212354B4 (en) | Low impedance load switch with output current control | |
DE102008039351B3 (en) | Circuit arrangement for operating at least one semiconductor light source | |
EP0967714B1 (en) | Switching power supply | |
DE69914166T2 (en) | CONTROL DEVICE AND ELECTROMAGNET WITH AN ELECTROMAGNET POWER SUPPLY SWITCHED TO THE ELECTROMAGNET POWER SUPPLY | |
EP1867035B1 (en) | Method for operating a switched mode power supply with the recovery of primary scattered energy | |
EP2110938B1 (en) | Control circuit on the primary side of an electronic power converter having a transformer without auxiliary winding with a regulation based on the secondary side current flow duration | |
WO1995009476A1 (en) | Fly back converter | |
DE3912849C2 (en) | ||
DE10249802A1 (en) | DC voltage converter has inductance connected to input at one end, to reference potential and output via two switches at other end, arrangement for controlling switches to regulate output voltage | |
EP1652286B1 (en) | Switched-mode power supply | |
DE10207138A1 (en) | Circuit and method for improving the efficiency of a switching regulator | |
EP1658676B1 (en) | Circuit and method for conditioning a supply voltage containing voltage peaks | |
DE10334338A1 (en) | Controlled synchronous rectifier for regulating an output voltage of a switched-mode power supply | |
EP0978933B1 (en) | DC-DC converter | |
EP1532726B1 (en) | Switching controller | |
EP0301386A2 (en) | Switching power supply | |
DE3941420C1 (en) | ||
AT411506B (en) | SWITCHING REGULATOR | |
DE102004035248B4 (en) | resonant converter | |
DE19530064A1 (en) | Controlled converter with at least two secondary circuits | |
AT504245A1 (en) | SWITCHING REGULATOR | |
EP1018207B1 (en) | Switched-mode power supply device with a starting circuit | |
DE10339478B4 (en) | Circuit and method for processing a supply voltage with voltage spikes |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20060113 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT CH DE LI |
|
DAX | Request for extension of the european patent (deleted) | ||
RBV | Designated contracting states (corrected) |
Designated state(s): AT CH DE LI |
|
17Q | First examination report despatched |
Effective date: 20100115 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: SIEMENS AKTIENGESELLSCHAFT |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R079 Ref document number: 502004012938 Country of ref document: DE Free format text: PREVIOUS MAIN CLASS: H02M0001000000 Ipc: H02M0001360000 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
RIC1 | Information provided on ipc code assigned before grant |
Ipc: H02M 1/36 20070101AFI20110304BHEP Ipc: H02M 3/335 20060101ALI20110304BHEP |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT CH DE LI |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 502004012938 Country of ref document: DE Effective date: 20111201 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20120706 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 502004012938 Country of ref document: DE Effective date: 20120706 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20120831 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20120831 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 20170710 Year of fee payment: 14 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20171019 Year of fee payment: 14 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 502004012938 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MM01 Ref document number: 527744 Country of ref document: AT Kind code of ref document: T Effective date: 20180805 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180805 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20190301 |